Coyne: Psychotherapy adds little in largest study of anorexia ever

[Esther12]

http://blogs.plos.org/mindthebrain/...dynamic-therapy-better-routine-care-anorexia/

This follows on from another Coyne blog Dolphin posted here:

http://forums.phoenixrising.me/inde...-therapy-vs-psychoanalysis-for-bulimia.27528/

There were a few bits that semi stood out as of interest to people here, but I wasn't really sure what to take. It is quite long, so may not be worth people reading for themselves unless they have a particular interest.

They used BMI as an outcome measure, so that avoids a lot of the problems that people here tend to be concerned with:

The spinning of the trial in favor of focal psychodynamic treatment.

The preregistration of the trial listed BMI at the end of treatment as the primary outcome. That means the investigators staked any claims about the trial on this outcome at this time point. There were no overall differences.

The preregistration also listed numerous secondary outcomes: the Morgan-Russell-criteria; general axis I psychopathology (SCID I) ; eating disorder specific psychopathology (SIAB-Ex; Eating Disorder Inventory-2) severity of depressive comorbidity (PHQ-9); and quality of life according to the SF-36. Not all of these outcomes are reported in the article, and for the outcomes that are reported, almost all are not significantly different at any timepoint.

The authors’ failure to single out one or two of these variables a priori (ahead of time) sets them up to pick-the-best hypothesizing after results are known or HARKING. We do not actually know, but there is a high risk of bias.

We should be highly skeptical about post hoc exploratory analyses of variables that were not pre-designated as outcomes, in either primary or secondary analyses.

This is a strange bit:

An extraordinary “optimized” treatment as usual.

Descriptions in the preregistered study protocol, press releases, and methods section of the article do not do justice to the “optimized” treatment as usual. The method section did not rouse particular concern from me. It described patients assigned to the treatment as usual being provided with a list of psychotherapists specializing in the treatment of eating disorders and their family physicians assuming an active role in monitoring and providing actual treatment. This does not sound particularly unusual for a comparison/control group. After all, it would be unethical to leave women with such a threatening, serious disorder on a waiting list just to allow a comparison.

But then I came across this shocker description of the optimized routine care condition in the discussion section:

Under close guidance from their family doctor—eg, regular weight monitoring and essential blood testing—and with close supervision of their respective study centre, patients allocated optimised treatment as usual were able to choose their favourite treatment approach and setting (intensity, inpatient, day patient, or outpatient treatment) and their therapist, in accordance with German national treatment guidelines for anorexia nervosa.11 Moreover, comparisons of applied dosage and intensity of treatment showed that all patients— irrespective of treatment allocation—averaged a similar number of outpatient sessions over the course of the treatment and follow-up periods (about 40 sessions). These data partly reflect an important achievement of the German health-care system: that access to psychotherapy treatment is covered by insurance. However, patients allocated optimised treatment as usual needed additional inpatient treatment more frequently (41%) than either those assigned focal psychodynamic therapy (23%) or enhanced cognitive behaviour therapy (35%).

OMG! I have never seen such intensive treatment-as-usual in a clinical trial. I doubt there is anything like this treatment would be available elsewhere in the world as standard care.

This description raises a number of disturbing questions about the trial:

Why would any German women with anorexia agree to be in the clinical trial? Although a desire to contribute to science is sometimes a factor, the main reason for patients entering clinical trials are because they think they will get better treatment and maybe because they think they can get their preferred treatment which they cannot get it elsewhere. But, if this is the situation of routine care in Germany, why would eligible women not just remain in routine care without the complications of being in a clinical trial?

In short, the manualized treatments were doomed to null findings in comparison to treatment as usual. The only thing really unexpected about this trial is that all three conditions did so poorly.

What is a comparison/control group supposed to accomplish, anyway?

Investigators undertaking randomized controlled trials of psychotherapies know the necessity of comparison/control groups, but they generally seem generally unaware of the implication of the choice of a comparison/control group.

Most evidence-based treatments earned their status by proving superior in a clinical trial to a control group such as wait list or no treatment at all. Such comparisons provide the backbone to claims of evidence-based treatments, but are not particularly informative. It may simply be that many manualized, structured treatments are no better than other active treatments patients have similar intensity of treatment, positive expectations, and attention and support.

Some investigators, however, are less interested in establishing the efficacy of treatments, then in demonstrating the effectiveness of particular treatments over what is already being done in the community. Effectiveness studies typically find small effects been obtained in straw-man comparisons between treatments and the weak effects observed in control groups.

But even if their intention is to conduct an effectiveness study, investigators need to better describe the nature of of treatment as usual, if they are to make reasonable generalizations to other clinical and health system context.

We know that the optimized treatment as usual was exceptionally intensive, but we have no idea from the published article what it entailed, except lots of treatment, as much as what was provided provided in the active treatment conditions. It may even be that some of the women assigned to optimized treatment obtained therapists providing much the same treatment.

Again, if all of the conditions had done well in terms of improved patient outcomes, then we could have concluded that introducing manualized treatment does not accomplish much in Germany at least. But my assessment is that none of the three conditions did particularly well.

The optimized treatment as usual is intensive but not evidence-based. In my last blog post, we viewed a situation in which less treatment proved better than more. Maybe the availability of intensive and extensive treatment discourages women from taking responsibility for their health threatening condition. They do not improve, simply because they can always get more treatment. That is simply a hypothesis, but Germany is spending lots of money assuming that it is incorrect.